Abstract: The present invention provides a precision miter gauge for orienting and positioning a workpiece relative to a cutting tool. The miter gauge reduces positioning errors and improves repeatability. The miter gauge includes a base and a body pivotably connected to the base. A positioning edge of the body contains a plurality of teeth between which a positioning member connected to the base is inserted and locked in place. In this manner, relative movement of the positioning body relative to the base is inhibited.

Abstract: A method for making a paintball grenade includes adding a thickening agent, a coloring agent, and a mixing agent to an enclosure, such as a balloon. Water is added to the enclosure and combines with the thickening agent and the coloring agent to form a colored, gelatinous liquid. The mixing agent facilitates the mixing of the thickening agent and the coloring agent with the water. The enclosure can be thrown or launched during a game of paintball to eliminate players on an opposing team from the game.

Abstract: An apparatus and method for determining the concentration of alcohol present in a gaseous mixture wherein an electronic device employing a fuel cell determines the concentration of alcohol present in the gaseous mixture is disclosed. In particular, the device may be used to determine a person's sobriety by determining the alcohol concentration in a breath sample. To determine the alcohol concentration, the device must be able to accurately determine the volume of breath in the breath sample. The device controls the volume of the breath sample by measuring the pressure of the breath flow through the device and, in response to the pressure, electronically controlling a valve diverting a portion of the breath flow into the fuel cell. One application of the invention is a sobriety interlock for a machine where the machine remains disabled unless the operator is first determined to have an alcohol concentration below a predetermined level.

Abstract: An apparatus and method for determining the concentration of alcohol present in a gaseous mixture wherein an electronic device employing a fuel cell determines the concentration of alcohol present in the gaseous mixture is disclosed. In particular, the device may be used to determine a person's sobriety by determining the alcohol concentration in a breath sample. To determine the alcohol concentration, the device must be able to accurately determine the volume of breath in the breath sample. The device controls the volume of the breath sample by measuring the pressure of the breath flow through the device and, in response to the pressure, electronically controlling a valve diverting a portion of the breath flow into the fuel cell thereby indicating and ensuring that a predefined requisite amount of breath flow has passed thru the fuel cell.